#include <string.h>
#include <stdio.h>

int     opterr = 1,             /* if error message should be printed */
optind = 1,             /* index into parent argv vector */
optopt,                 /* character checked for validity */
optreset;               /* reset getopt */
char    *optarg;                /* argument associated with option */

#define BADCH   (int)'?'
#define BADARG  (int)':'
#define EMSG    ""

/*
* getopt --
*      Parse argc/argv argument vector.
*/
int
getopt(int nargc, char * const nargv[], const char *ostr) {
	static char *place = EMSG;              /* option letter processing */
	const char *oli;                        /* option letter list index */

	if (optreset || !*place) {              /* update scanning pointer */
		optreset = 0;
		if (optind >= nargc || *(place = nargv[optind]) != '-') {
			place = EMSG;
			return (-1);
		}
		if (place[1] && *++place == '-') {      /* found "--" */
			++optind;
			place = EMSG;
			return (-1);
		}
	}                                       /* option letter okay? */
	if ((optopt = (int)*place++) == (int)':' ||
		!(oli = strchr(ostr, optopt))) {
		/*
		* if the user didn't specify '-' as an option,
		* assume it means -1.
		*/
		if (optopt == (int)'-')
			return (-1);
		if (!*place)
			++optind;
		if (opterr && *ostr != ':')
			;//(void)printf("illegal option -- %c\n", optopt);
		return (BADCH);
	}
	if (*++oli != ':') {                    /* don't need argument */
		optarg = NULL;
		if (!*place)
			++optind;
	} else {                                  /* need an argument */
		if (*place)                     /* no white space */
			optarg = place;
		else if (nargc <= ++optind) {   /* no arg */
			place = EMSG;
			if (*ostr == ':')
				return (BADARG);
			if (opterr)
				;// (void)printf("option requires an argument -- %c\n", optopt);
			return (BADCH);
		} else                            /* white space */
			optarg = nargv[optind];
		place = EMSG;
		++optind;
	}
	return (optopt);                        /* dump back option letter */
}